Modern times
Quote (RAT5)
There was one poster who was concerned about derate, assumed temp, and improved climb all together. Is that possible? I thought improved climb required full umph, or did I misunderstood the comments? I doubt improved climb was in play here, as excess runway is required, and I doubt 2011m gives any excess.[/UNQUOTE]
Yeah Rat, in days of old, improved climb was only used with full thrust, to improve one engine out climb performance by using excess available runway length to accelerate to a higher Vr, and thus to a higher V2.
Today, the bean counters have invented the method to use excess runway length for a greater reduction of thrust, so that takeoff performance only JUST satisfies regulations.
As far as derate plus assumed temperature is concerned, that sounds more frightening than it is: if the situation calls for e.g. 85 percent N1, that could be achieved with e.g. Derate 2 at 35 degrees assumed, or Derate 1 at 48 degrees assumed, but e.g. Full rated at maximum assumed might for instance not be below 87 percent N1. So, in all cases, used thrust would be at least the same.
Biggest consequence of a derate would be subsequent automatic use of derated Climb thrust after thrust reduction point.